What animals are not vertebrates?
There are seven primary groups of invertebrates in the animal kingdom. They are sponges, ctenophores, cnidarians, echinoderms, worms, mollusks and arthropods.
The majority of animals on earth are invertebrates. The vertebrates – mammals (such as ourselves), birds, reptiles, frogs and fish are only one group of thirty that make up the animal kingdom . Therefore all the vertebrates put together are only a tiny proportion of the species of animals on earth. All the rest, well over 90%, are invertebrates.
The majority of animal species are invertebrates; one estimate puts the figure at 97%. Many invertebrate taxa have a greater number and variety of species than the entire subphylum of Vertebrata .
Vertebrates are animals that have a backbone or spinal column, also called vertebrae. These animals include fish, birds, mammals, amphibians, and reptiles. How are they classified? Vertebrates are classified by the chordate subphylum vertebrata. Invertebrates are any other animal that is classified outside of that class.
Animals without backbones are called invertebrates. They range from well known animals such as jellyfish, corals, slugs, snails, mussels, octopuses, crabs, shrimps, spiders, butterflies and beetles to much less well known animals such as flatworms, tapeworms, siphunculids, sea-mats and ticks.
All vertebrate animals (fish, amphibians, reptiles, birds and mammals) have internal skeletons. Although they look quite different at first glance, they share some basic characteristics.
Mammals are vertebrates, which means that they all have backbones (spines). All mammals, except some sea cows and sloths have seven bones in their necks. This includes giraffes who have VERY long spines! Their necks can be 6 1/2 feet long, but they’re still made up of just seven bones.
Sponges, corals, worms, insects, spiders and crabs are all sub-groups of the invertebrate group – they do not have a backbone. Fish, reptiles, birds, amphibians and mammals are different sub-groups of vertebrates – they all have internal skeletons and backbones.
